Temporary Reversal of Blood Flow During Transcarotid Artery Revascularization Does Not Change Brain Electrical Activity in Lead-In Cases of the ROADSTER 1 Multicenter Trial.

PURPOSE: To evaluate any intraoperative electroencephalographic (EEG) changes accompanying reversed flow with the ENROUTE Transcarotid Neuroprotection System during transcarotid artery revascularization (TCAR). METHODS: A post hoc analysis was performed of the first 81 consecutive lead-in patients (mean age 72.8±8 years; 61 men) enrolled in the ROADSTER 1 trial at 5 participating institutions. All patients had high-grade carotid artery stenosis [53 (59.3%) left sided; 12 (14.8%) contralateral occlusions] and high-risk criteria for carotid endarterectomy. A third had symptoms of either stroke (13, 16.0%) or transient ischemic attack (14, 17.3%). This subset of early patients underwent EEG monitoring to detect any cerebral changes during reversed flow as an added safety measure mandated by the ROADSTER 1 trial protocol. RESULTS: Mean flow reversal time was 12.9±8.2 minutes. The goal mean arterial pressure during reversed flow was 100 mm Hg, but 7 (8.6%) patients suffered hypotension. One (1.2%) patient had slight EEG changes secondary to blood pressure fluctuation; these resolved with blood pressure elevation. No other EEG changes were noted. One (1.2%) patient had a postoperative stroke and another (1.2%) had postoperative myocardial infarction (MI), leading to 2.5% 30-day stroke/death/MI rate. CONCLUSION: Temporary reversal of blood flow during TCAR is a safe maneuver and does not cause cerebral ischemia in the vast majority of patients, including those with contralateral carotid occlusion. Carotid stenting performed with reversed blood flow mitigates cerebral embolization and periprocedural stroke without concern for brain ischemia.

Below the belt: sensory mapping and monitoring in the sacral-pudendal region.

Originally described in 1982, scalp somatosensory evoked potential responses can be recorded after stimulation of multiple different pudendal nerve- and sacral root-supplied structures. The resulting P40 response is usually the highest amplitude at Cz. Responses are generally easy to resolve and therefore should be of equivalent ease to follow for neurophysiologic intraoperative monitoring versus lower limb peripheral nerve somatosensory evoked potentials (e.g., tibial or fibular [peroneal] nerves), but sizeable reports of pudendal somatosensory evoked potential monitoring are few. Direct orthodromic sensory nerve action potential recording from the cauda equina in response to single such sacral stimuli has been reported of utility for preserving roots that participate in urinary control during dorsal rhizotomy procedures for spasticity. Technical application of both techniques is quite straightforward. As in most areas of neurophysiologic intraoperative monitoring, there are no well-constructed historical control series informing use of these techniques and, certainly, no clinical trials. Given the socially devastating consequences of urinary and anal continence disturbances and a fairly high rate of functional postoperative disturbances when sacral roots are manipulated, this field begs more active clinical investigation.

The possibility of clinical trials in neurophysiologic intraoperative monitoring: a review.

There is substantial controversy regarding the current evidence basis of practice for neurophysiologic intraoperative monitoring (NIOM). The randomized controlled trial is clearly the highest level of evidence of efficacy for intervention in health care. The low rate of new neurologic deficits in many types of surgeries for which NIOM is considered means that statistical power would require tremendous trial size; however, there are some surgeries with higher rates of new neurologic deficit for which this effect is not the case. For some surgeries, NIOM has clearly become the standard of care, and there would be no equipoise in randomization to NIOM versus no NIOM at all. For this situation, careful study design to permit comparison of different NIOM approaches or anesthesiological regimens might permit the achievement of equipoise. In oncological contexts, NIOM is often used to delimit the extent of resection to avoid motor new neurologic deficits, but this approach may lower complete resection rates; in this setting, a randomization to restrictive versus permissive NIOM parameters limiting resection could test the long-term advantages of motor versus oncological outcomes. Clearly, randomized controlled trial demonstration of NIOM efficacy for the prevention of new neurologic deficits would be difficult to accomplish. However, with careful choice of surgical population and randomization design, prospective trials would in fact not be impossible.

Continuous and routine EEG in intensive care: utilization and outcomes, United States 2005-2009.

OBJECTIVES: To evaluate the effect of intensive care unit continuous EEG (cEEG) monitoring on inpatient mortality, hospital charges, and length of stay. METHODS: A retrospective cross-sectional study was conducted using the Nationwide Inpatient Sample, a dataset representing 20% of inpatient discharges in nonfederal US hospitals. Adult discharge records reporting mechanical ventilation and EEG (routine EEG or cEEG) were included. cEEG was compared with routine EEG alone in association with the primary outcome of in-hospital mortality and secondary outcomes of total hospital charges and length of stay. Demographics, hospital characteristics, and medical comorbidity were used for multivariate adjustments of the primary and secondary outcomes. RESULTS: A total of 40,945 patient discharges in the weighted sample met inclusion criteria, of which 5,949 had reported cEEG. Mechanically ventilated patients receiving cEEG were younger than routine EEG patients (56 vs 61 years; p < 0.001). There was no difference in the 2 groups in income or medical comorbidities. cEEG was significantly associated with lower in-hospital mortality in both univariate (odds ratio = 0.54, 95% confidence interval 0.45-0.64; p < 0.001) and multivariate (odds ratio = 0.63, 95% confidence interval 0.51-0.76; p < 0.001) analyses. There was no significant difference in costs or length of stay for patients who received cEEG relative to those receiving only routine EEG. Sensitivity analysis showed that adjusting for diagnosis-related groups (DRGs) for any neurologic diagnoses, DRGs for neurologic procedures, and specific DRGs for epilepsy/convulsions did not substantially alter the association of cEEG with reduced inpatient mortality. CONCLUSIONS: cEEG is favorably associated with inpatient survival in mechanically ventilated patients, without adding significant charges to the hospital stay.

The American Academy of Neurology's top five choosing wisely recommendations.

OBJECTIVE: To discuss the American Academy of Neurology (AAN)'s Top Five Recommendations in the Choosing Wisely campaign promoting high-value neurologic medicine and physician-patient communication. The AAN published its Top Five Recommendations in February 2013 in collaboration with the American Board of Internal Medicine Foundation and Consumer Reports. METHODS: A Choosing Wisely Working Group of 10 AAN members was formed to oversee the process and craft the evidence-based recommendations. AAN members were solicited for recommendations, the recommendations were sent out for external review, and the Working Group members (article authors) used a modified Delphi process to select their Top Five Recommendations. RESULTS AND RECOMMENDATIONS: The Working Group submitted 5 neurologic recommendations to the AAN Practice Committee and Board of Directors; all 5 were approved by both entities in September 2012. Recommendation 1: Don't perform EEGs for headaches. Recommendation 2: Don't perform imaging of the carotid arteries for simple syncope without other neurologic symptoms. Recommendation 3: Don't use opioids or butalbital for treatment of migraine, except as a last resort. Recommendation 4: Don't prescribe interferon-ß or glatiramer acetate to patients with disability from progressive, nonrelapsing forms of multiple sclerosis. Recommendation 5: Don't recommend carotid endarterectomy for asymptomatic carotid stenosis unless the complication rate is low (<3%).